I think answer should be carbon dioxide
Answer:
Molar mass→ 0.930 g / 6.45×10⁻³ mol = 144.15 g/mol
Explanation:
Let's apply the formula for freezing point depression:
ΔT = Kf . m
ΔT = 74.2°C - 73.4°C → 0.8°C
Difference between the freezing T° of pure solvent and freezing T° of solution
Kf = Cryoscopic constant → 5.5°C/m
So, if we replace in the formula
ΔT = Kf . m → ΔT / Kf = m
0.8°C / 5.5 m/°C = m → 0.0516 mol/kg
These are the moles in 1 kg of solvent so let's find out the moles in our mass of solvent which is 0.125 kg
0.0516 mol/kg . 0.125 kg = 6.45×10⁻³ moles. Now we can determine the molar mass:
Molar mass (mol/kg) → 0.930 g / 6.45×10⁻³ mol = 144.15 g/mol
Answer:
Explanation:
<u><em>Given :</em></u>
Mass in grams = m = 42 g
Molar Mass = M = 12
<u><em>Required:</em></u>
No. of moles = n = ?
<u><em>Formula :</em></u>
m = m / M
<u><em>Solution:</em></u>
n = 42 / 12
n = 3.5 moles
Answer:
D.
Explanation:
Hydroxide ions are produced when acid reacts with a base under a Ph value of more than 7. Hydroxide ions are negatively charged ions which are released in the aqueous solution during titration process. It a oxygen and hydrogen atom covalent bond.
Use the ideal gas law PV = nRT and manipulate it to solve for n. PV/RT = n.
Convert to SI units:
660ml -> 0.660 L
27 degrees -> 300 K
Leave Pressure as is
Use 62.36368 for R becuase you are using mmHg for Pressure.
Now plug into the equation to get about 0.025928 mols. Divide the 3.30 grams by the mols to get about 127 g/mol.
